Abstract
Power transformers are the most significant and vital component of the power delivery system. Its reliability and performance remain of great importance to the utilities. Irrespective of the failure rate, transformers are also of high concern from the point of asset management. Sudden failure of a large transformer may cause interruption in power supply resulting in a high repair costs, revenue losses as well as environmental and collateral damages. Transformer operating with load and ambient temperature higher then its design characteristics accelerates the aging process and involves high risk of catastrophic failures. Over voltages and short circuits have also a significant contribution towards transformer deterioration. Condition based maintenance (CBM) is an important tool in the asset management that would allow the transformer to operate according to its actual practicable efficiency. Better transformer management could be achieved with online monitoring, routine diagnostics, and CBM. Total life cycle cost including routine maintenance, reconditioning, major refurbishment and condition monitoring stands important for strategic, economic and technical assessment as well as asset management strategies. Transformer's performance, reliability and technical life can be increased with the implementation of correct operational criteria (condition based) and management strategies. Also transformer's timely relocation and retirement/ replacement can be planned.